GB512665A - Improvements in and relating to electric lamps or the like - Google Patents

Abstract

512,665. Incandescent lamps baling closed bulbs. BRITISH THOMSON-HOUSTON CO., Ltd. March 1, 1938, No. 6429. Convention date, March 2, 1937. [Class 39 (ii)] Relates to means for capping an electric incandescent lamp bulb and attaching the leading- in wires therefor and comprises assembling a metal base shell 10, Fig. 1, (shown of the screwcap type) and a metal eyelet 11 with a ring 18 or a tube of glass between them, each metal part having a lead wire 21, 20 secured thereto, and then applying heat to unite the metal parts by fusion of the glass. Into this cap assembly the neck 30, Fig. 3, of the bulb 28 is inserted and heat is applied to the shell to fuse the portion of the neck located therein. To seal the neck closely to the shell, air under pressure is supplied to the bulb through a hole 17 in the eyelet so as to force the heat-softened neck into contact with the shell. The interior of the bulb is then exhausted through the hole 17 and gas admitted, if desired. Finally, the hole is sealed by fusing down a short length of the glass tube through which the bulb was exhausted or by fusing glass beads. placed. in the cup-shaped end of the eyelet or in its interior. A modification (Fig. 9, not shown) is described for a double-filament lamp. Specifications 26,292/04, [Class 39], 420,783, 433,233 and 439,593 are referred to.